One example of a prior art missile launch is where a missile is launched vertically, using a piston powered launch pad at a launch site. This is known as a “cold launch” as the missile motor is not used to launch the missile. Once the missile is in the air, it can be turned to be horizontal using lateral gas thrusters. However, if the missile motor fails the missile would fall (an inert descent situation) and would land on or near the launch site. An example of such a launch is described in US 2006/0107828.
A second example of a prior art missile launch uses a similar missile to that of the first example. However, this second example missile has a rotatable thrust deflection device (called a “jetavator”) attached to a nozzle of a lateral gas thrusters. A representation of the jetavator 1 is shown in FIG. 1. The jetavator deflects some of the lateral flow from the nozzle 2 to provide an axial (longitudinal) component of thrust flow. The jetavator 1 is rotatable in relation to the nozzle 2. This means that the missile rotates laterally to be horizontal (as before) but also moves axially (longitudinally). This moves the missile horizontally away from the launch site and is advantageous for safety and/or tactical reasons. Therefore, if the missile motor should fail, the missile would not fall and land on or near the launch site. It is also possible to have more than one jetavator, each jetavator deflecting lateral flow from a different nozzle.
However, the control system required to control the rotation of the jetavator(s) to provide the required amount of axial thrust flow is complex. It is also necessary to provide sealing (shown by reference numeral 3 in FIG. 1) to seal the jetavator over the nozzle. In addition, it is difficult to retrofit such a jetavator and control system to an existing missile due to requiring significant space and requiring a significant redesign.